Automatic release coupling



April 20,1926. 1,531,457

I W. A. MUELLER AUTOMATIC RELEASE COUPLING File-d July 26- 1925 4Sheets-Sheet l wm .D Low .W7 rf u HUM.

u a i: I 'N /Y'S a I Ar j? "l li; t .Af ih I i WITNESSES VY WU /lf//M iPf23 @B21/@y A TTORNE YS April 20,1926. l 1,519,467

- l `w. A. MUELLER l AUTOMATI C RELEASE GOUPLING Filed Jply 26, 1925 4sheets-sheet z A TTORNE YS l April 20 1926. 1,581,467

. w. A. MUELLER AUTOMATIC RELEASE COUPLING Filed July 26' 1923 A 4Sheets-Sheet 3 April 20,1926.` 1,581,467

W. A. MUELLER AUTOMATI C RELEASE COUPLING Amann/sys coupling,

Patented Apr. 20, 192.6... Y

UNITED STA-gis i AUTOMATIC RELEASE. courir-ams.

Application mea Jury ze, 1923; .Seriali-nq. 654,090.

T0 all whom it may concern: rvBe itv knownV that I, l/VILLIAM ANTONMUELLER, a citizen of the United States,

and aresident of Aberdeen, in the county y y l the adaptation oftheinventionbto aconof Brown and State of South Dakota, have inventedcertain new a-nd use'l'ul ilmprovef ments in Automatic VReleaseCouplings, of

which the following is" a specification.

` My invention relates to improvements in couplings adapted for use inagricultural pursuits and Yit consists of the constructions,combinations and arrangements herein described and claimed. Y

An object of the invention is to'provide a coupling to be used between atractor and a plow which' coupling is made in sucha Way that it Willautomatically rel-ease the tractor should Vthe ploiv'present abnormalresistance as in instances when it [becomes stuck.

" Another' object of the invention is to pro vide an automatic releasecoupling-for the purpose described hax'ung a dog which is adapted tomake a complete revolution upon becoming released, and-at the end ofsaid revolution occupy a Vre' set position.'

Other objects and advantages will appear in the followingspecication,reference heaccompanying drawings7V in Fig. 1 is a perspective viewvillustrating a typical forml of the automatic releasel coupling, y

Fig. 2 is a longitudinal section .of Fig. l, parts being in elevation,illustrating the action when the dog is v,released 4by, the latch andalso illustratingfhoivthefdog turns hack tothe voriginalpositionat theend of the revolution aforesaid,

Fig. 3 is a detail cross section taken on the line fla-3 of' Fig. 1andshou'ing the peculiar constructionv` oi: the pivot pini' Fig. 4l is alongitudinal section, partly in elevation, illustrating a modilicationofthe Fig. 5 is a'longitudinal 'section' of another modification ot thecoupling wherein the head of the latch bolt 'engages the dog, f Fig. 6is a similar view Villustrating the action upon the releaseV of rthedog,l

Fig. 7 is -a detail side elevation of a further modification involvingthe use of a horn toI prevent the pulling link from moving hack over thevside arms,v

Fig. 8 is a perspective view of a modification 'inthe construction ofthe side anus,

.. telescopicA pin,

` @cation Y0f thegdegof draw hart.I`A` y Fig. 911s Va* perspective Viewillustrating pling'fhetween a tractor l and an Oliver No.

Fig. v10 is a detll perspectivevietv .of the rig-cn is a Sleeve inwhichsaid pin telescopes,

detail perspective. viewV .of .the

` yillustrating van arrangement by .Whichfthe Y s1de`ar1 s areapplicable to almost anyfforim "Fig 12 is Idetail perspective viewshoiving how the pull linkof'the tractor attaches to; the clevis inFig.` Q,

.'Fig. 13 is a l boltinay be turned to release thedog. Fig.i 14is aperspective-view of the modiication inFig. l13 .showing how lvvillloe'attached to the vh itch ofthe John DeereNo.

"plein v f Fig. 15- 'isa longitudinal vsectionof an- 'othermodificationr of the coupling. illustratna .he ,use ef seoseneok Sidearms and a Straight dos, Y z* F ig, 16 is a. viewr similar to Fig. 1 5,illustrating a further modification inthe disposition o f the pull linkopening v-inthedog,

Fi g.. 17 vis detail perspective view; ofthe Alatch bolt as used inFigs. 18 to- 15,

1; Fig. Y18 isa perspective view oftlrelatch bolt 'as used in Fig. 16,`and Fig; 41 9 isa detail-.view of a further.Imodi- Ity willbefQhviousftofthe yrfller from the '.nstudeal seten illustra@ `ing.another -inodification in which thelatch vforegoing.brieflIdescriptions of the views ,inf

.the drawings, tliatthe objectof the vinvention is carried out by avarietyof typesof the automatic coupling.' The 'various modivlicationsare presented in order to show how the coupling is adaptable torvariousforms of plow `draw bars and how the dog may be released inVvari n1s Ways and still preserve `the identityv of the invention. Inorder to keep thevvarious constructions separate lthey are described inthe order that they' appear in the drawings.

The modification in Figs.1 to 3 illustrates 'the use of a dog 1j' whichis pivoted on a pin 2 between sidearms 3 and 4.' The dog 1 ishent inasomewhatpeculiar manner, as lshown in Fig. 2. It is oit a distorted U-shape, and whenv operatively mounted on the pivot pin 2the arrangementis suchA that the Curve 5 at Whichth'e pull occursyis situated at apoint Belo-W the'pi'vet.

lbe loose, as may be desired.

I l The' link 6 is intended to "attach to a tractor or other availablepulling power, and when the pull occurs (Fig. 2) the shoi't end of thedog tends to move'liorward, while the longend tends to swing downward.This downward moving tendency ischecked by suitable holding meansinorder that the dog may not be released in ordinary operation. Y However,this holding means is so arranged that it will release the dog onoccasions when the plow, to which the reader may suppose the coupling tobe attached, is put under such an unusual strani that there is danger ofbreaking some other part( This holding means consists of a bolt 7 to,

head 11 of the bolt.

In the case now under consideration, the upward pressing tendency of thespring9 moves a'latch 12 against the under side or" the side arms 3 and4. This latch has a hole 13 through which the holt 7 extends. VIt isbeneath the latch that the head l1 has engagement. The latch includeslinks 14which extend up on each side of the side arms andV have rockingsupport on a shaft 15 which in turn is carried by brackets 16.

These brackets Vare secured by the same Vbolts 17 which hold the sidearms 3 and 4 and the spacer bar 18 together. The spacer bar may be madein any one of a number of ways. In the present instance it extends outfat the back of the side arms and lhas several openings 19 providingconvenient places where the draw bar of a plow may be attaclied. Thestrength of the extended part .of the spacer maybe such as t0accommodate the different tions.

In practice, the spring 9 is intended to be quite strong', in fact,strong enough to resist plow draw bar constructhe downward movingtendency of the dog l against the latch 12. rlhe .spring 9 is thereforestrong enough to withstand the ordinary or normal pulling pressure bywhich the plow or other implement is drawn forwardly over the ground.Now, should the plow oi' other implement stick and thus call for theexercise of abnormal pulling Vpower on the part ot the tractor or otherpulling agent, the spring 9 will yield so that the latch l2 moves downand permits the release of the dog 1. This release will causeV the dog 1to spin around in the direction olf the arrow (Fig. 2). Thejdog willmake a complete revolution. In themeantion. Jlhe dog is then inreadiness to again receive the link G when ordinary conditions arerestored.

lt is to be observed that the pivot pins 2 have provisions for' keepingthe link (5 troni slipping back `over the side arms 3 and 4.

At one end the pivot pin 2 has an'otlset 20.Y

rl`he other end of the pin; is straight (F 3) but is provided with aVrocker 2l which has a projection 22 at one side serving the samepurpose as the odset 20. rIhe rocker 21 is held in place by aV cotterpin 23. The reader can readily see that the offset 20 and projection 22will readily'ke'epk the link 6 from slipping. v

rl'he modilication in Fig. 4 is closely related to the foregoingmodification. Only so much of the dog` 24 is shown as is necessary toshow how it engages the head 25 ot' the latch bolt 2G. instead of usingthe shaft 27 as a mounting for' links, as in Fig. 1, it is used as themounting for a plate 2S which Y extends up between a pair of lock nuts29 bv means ci' which the bolt 26 and the plate' 28 are securedtogether. The bolt 26 and the plate 28 `are therefore integral andconstitute the equivalent ot the latch12 in Fig. l.

The bolt 26 carries a sleeve 30 against which one end of the spring 3lbears. The other end ot the spring bears against the top of the sidearms, oi which only the one 32 may be seen at the back of the bolt inFig. 4. The spacing 4necessary for the swinging ot the dog 24 betweenthe side arms Vis preserved by a'bar 33 which, like the bar 18 in Fig 1,is secured by bolts 34 which also hold the latch brackets 85 in place.Excessive downward pressure on the dog 24'inrthe direction of the arrowwill cause the displacement of theV latch 25 against the tension'otthespring 3l, whereupon tlie dog is released and may swing around in acircle, as suggested in `Fig. 2 until reengagement is had.

The modification in Figs. 5 to 7 shows how the functions ot a latch maybe preserved without actually employing a latch, as is done in Figs. 2and V4. Here, the latch bolt 36 has a head 37 which supports the longarm of the dog 38 during ordinary operating circumstances such asmentioned before.

rlhelatch bolt issustaincdby a .spring 39 which in turn presses againsta nut 40 on the threaded end of the bolt. The nut is adapted to increaseor diminish the tension oi the spring 39 upon occasions. y 'i Adistinction is to beV noted between the shape of the end ot the dog inFig. 5 and in the foregoing modification. in the latter instances theend ot the dog is beveled, whereas in Figs. 5 and 6, the end isstraight. Reference is new being made to that endo" beveled sid'e'41 ofthe-spacer 42 and leaves anam'ple passageway for 'the dog.' Theldog nowswings aroundbn the pivot 43y as before,v andreturns to the originalVresting position against the-head off the latc-h.-v1nl Fig'.`

2, the end'ofz thef-fdog must be beveled inv orderthfat itl may pass theen d of the latch plate lfwhen in th'e'iposition shown in In Fig.(5l-lise 'fromplaying orsslipping backwover the side l arms 46.-' Thishorn is the equivalent ofthe Voffset andthe projection 22 in Fig. Sinsoy far as 'function is concer-ned. LrBhe vhornV confsists ofnothinginore than a piece ofl'suitably shaped, perhaps bent,inetahapplied to the Asides Iof the arms 46 in the most convenientmanner7 and insuch a position asl to inter cept the link 45 should itfora-ny cause eX* hiloitfa tendency to flylback.'

' Themodication ifnxFi'g.8 illustrates an arrangement by meansof whichthe coupling may be readily applied to a 'Wide variety of draw bars.This' modification vdealsy mainlyr with the form ofthe side arms. In-

y stead of makingthese-separate,as in the precedingl .modjific'sations,`they now appear in the" shape of parallellmembers- 47 which vrare partof 'av bar which has-'been lbent or beveled at 48. The distance betweenthe side arms 47 is preserved by a spacer 49 which maybe either of theshape disclosed in Figs. 5 andk 6 or as in Fig. 1L n Thesty'le of pivotpin shown is that ofthe pivot pin in the first modification. The dog isomitted, inasmuch as use may be made of the dog ink any one` of themodifications Bolts 50"-secure the one-piece side armson top ofthe-drawbar of a plowor other implementt'o be` drawn.

The modification in- Figs. 9y to'12is `especially adapted foruse with a'plownow onv the market known as theOliver No. 7. The clevis 56 isseparated at the usual place off connection` with the draw plateQv andithefbolt 57 which formerly made the connection is now' used fto attachthe c'levis to a link 59 which may be regarded as-the equivalent of thepart 18 in 15 42 i-nv Fig. 5' and 49 in Fig'. 8, inasmuch afsit4 servesas 'a'spacer between chefs-ide arms601and 61. The spaei-ng between thesekside arms isl necessary for the proper Workin'gefftliedog 62, fasbefore'.-

is'made ofahorn'44 for the purpose lofpreventing the 'pulling link-.45.y

"L The dog has pivotal mountingbetween the `siderar'ms on 'axfu'lcrumlpin` 63 which may hel/similar to the fulcrum pin 2 of F=i-g. '1.Brackets"64V-support the shaft 65 on which links 66l and-the latch 67are 'pi-voted. 'The latc'hflis held .up by the'sprifng 68 lon Y fthelr'atchbolt 69 which, like the'bolitj 7 in Fig; 1,`has an' adjustablenut 70 by means of which the draw bar 51 is an outstanding bracket 71 towhich a. link` 7 2 is-iXedly connected. `This linkris in fact aUlboltfand in'one respect it f may be-regardedv` as the equivalent ofthe link 6 inV Fig. 1 inasmuch as it engages the dog vand isiadapted tobe releasedtherefrom. The' distinction between the arrangement in.'Figs4 9f'andj1 lies in thefa-ct Vthatin Fig. 9,

ythe link72 isy carried' by' the plow whereas" .in-Fig. S1 the link' iscarriedby the tractor.

However7 in both rcases,the link exerts a pulll againstf'thedog andtheprinciple of'- operation istherefore V'the' same. Mention hasbeen-made ofl the" fact that the draw plate k52 a-nd-'c'levis 56 areseparatedA inl Fig. 9.

It is noww necessaryy to support the draw yplate and consequently thevplow beam. This is accomplished by attaching the plate 73 of a pin 7 4vto the nowfree end ofthe draw plate. A rivet-orbolt 75'is useda* forthe purpose. The plate'78 has ahandle l7 6 'by tensionjof the `springmay be ."varfieol;Vv I Mounted on the side ofthe plow beam or means ofwhich the `plow beammay more l readily bev lifted and bywhich the pin74l may beinserted :in the sleeve 7 7.

`This .sleevelh'as an ear 78 through which the pin. 58 is inserted.Connection with the tractor or pulling power is made at' the pin 58.'IThe sleeve also has averticalea-r 79 through" which the pivot bolt57i-*passes so v' l as to `complete the lattachment of `the sleeve vtotheclevi's.v The pin '74hfa's telescopic engagement' with the sleeve.

Upon the occurrence yof -a resistance at the xplow greater than thespring 68 will support, the'spring glves way sothat the dog 62 rocksonrts-fulcrum 63 and releases the link 72. The telescopic pin 74.rwithdraws fro1n the sleeve'77, and when connections are reiestabl-ishedthe vhai-idle 76 is used to guide the pin back into the sleeve'77. Thedog 62 is Vadapted to" makev av ycomplete .revolution asf before, untilthe long entire-engages the latch 67 inV readiness jto again receive thelink72. l Fig. 12illustrates one'form of connection ofthe clevis'56 withthe tractor.. The draw bar `80 is a part' of thel tractor to which thepull link 81 is attached.l The pin 58 passes through boththe horizontalear 78 ofthe sleeve 77 and the clevis, the link 81 being held intlie'clevis bythe' pin. j

y The modificationin'Figs. 13 4and 14i`llusf trates a-nrarrangenient ofthecoupling on the Amarket as the John Deere No. 40. The beam S2(Fig-14;) of this plow hasa plate S3 attached thereto for the purposesof furnishing a vpivotal mounting for the bell crankSiL and a guide fortheclevis bolt 55.` This bolt is carried by links Swhich Vare, suspendedfrom one arm of the bell crank. The other arm of the bell cra-nk has arod 87 connected thereto so that by rocking the bell crank the clevisbolt 85 may be adjusted up and down in the slot 88 in the plate 83. f

In order to apply the invention, use is made of the clcvis bolt 85 as aVsupportfor the side arms `S9which are held apart by a spacer 90 so thatboth the dogv 91 and the latch bolt 92 may have ample room to workfreely. T he reader will understand that the automatic coupling iscapable of being adjusted up and down with the clevis boltrS by means ofthe bell crank and connecting rod.V Y Y A springf93 engages a nut 94 onthe bolt 92 at one end and the upper edge ofthe side arms at the otherend. This keeps the head 95 Vin engagement with the under side of theside arms so as to support the dog 91. In operation, the modification inFigs. 1.3 and 14k is much like that of the coupling in any of the other1forms of the invention.V The spring 93 will sustain the dog 91 until thedog is put under a strain greater' than the spring will stand.V'Iliereupon the spring will give, permitting the dog to move down tothe released position. In order that there may be ample room for thepassage of the dog, the forward end ofthe spacer 90 is beveled at 96.

' However, the latch in Figs. 13 and 14 is capable of another mode ofoperation. .Fastened between nuts 97 near the extremity of the bolt 92,is a handle 98. This handle is to be used in the event that it isdesired to manually disengage the dog 91. In such event,

, addition to turning the handle and the latch bolt, the latter may beinclined to the dotted line position against the beveled front edge ofthe spacer' 90 so as to provide ample room s ,for the passage of thedog. It is preferable liti that the handle 9S extend off to one side asshown in Fig. 14, so as to be out of the way in cases when the dog 91releases auton'iati.- cally. y

. The modifications in Figs.15 and 16 are so much alike that they may bedescribed together. The main difference between these forms and thosepreceding is that the side arms 99 are formed with a gooseneck 100 andthe dog 101 is made straight instead of according to the ,peculiarcurved formation in the various yother modifications. The gcosenek 100 snecessary to provide the yconnection between tractor and tained.

space for the` connection of the :pull link `102V Vwith the opening 103in the dog.V This opening is sof arranged thatV the line ofV pull belalike so far asthe provision of handlesllll is concerned, but there is aslight difference between the latehhead 112 of the, modification in Fig.15 and the head 113 in Fig. 1G.

Figs. 17 Land 18 illustrate the respective differences 'more clearly.The head y112 is rather fthick and joins immediately with the,

bolt 110. The headll is rather thin and is cut away at the back atlllis'o Vthat the-place of connection issomewhat on a .bias In vbothcases, a spring 115 holds thelatch head up underneath of the side arms`to thereby sustain the'dog 101 until such an .unusual pull occurs thatthe spring 115 way. ,Y Y :Y

The release of the ldog 101 may either be automaticA or manual. turnedoff to one side so that the swinging `must give The handles 111, are

of the dog may not be interfered with in the automatic release. Shouldit. be desired to manually disengage the -dog Vthe handle 111 may beturned ineither instance to the po-v sition shownin dotted lines in Fig.15.

Theoperationpmay be briefly :reviewed to advantage: VAill of theforms oflthe invention make use of a pivoted dog upon which a `pull orpressureis exerted in the operation of drawing a plow by means of'atractor.

. The dog forms the connecting link between the two, andas long as thedog remains 1n what may be regarded a normal position, the plow is sus-It frequently happens that a1 plow will become stuck, as for example instrikinga ency of the tractor is to pull so hard on the plow that someof the parts may break. VThe'dog is Vtherefore so arranged that it willreleasepwhenan abnormal pressure occurs. This yrelease is accomplishedautomatically and by `means of a spring latch which conboulder, stump,etc., whereupon the tendsists either of the pivoted members 12 and Y 67in Figs.` v1 Vand 9 respectively, or of the simplevlatch bolt as shown1n Figs. 4, 5, 13 and 15.

In all cases, thel dog latch is held up by a yeration of all ortheierma.

latch. As soon las the pulling .power-exceeds the strength of thespr-ing, ,the latch will` move toy the vfull line position in Fig. 2atwhich time the .dog is released and may f swing to make a completerevolution as suggested Abythe dotted lines,in readiness to re-engagethe latch 12 which supposedly has been restored to the former and dottedline position by the spring 9.

The foregoing typical description .o-f the operation .of the automaticcouplingk may well be supplemented by a brief description of thearrangement 'in Fig.` 9 inasmuch as: thiswintroduces elements not showninv anyV of the other modifications. The draw plate l52 and clevis 56are original partsof an Oliver No. 7 plow. In order to adapt thisyparticular plow to the automatic coupling, the clevis 56 is separatedfrom the original draw plate and the corresponding"connection is made bymeans of a sleeve 77 and pin 74. The elements' of which the Sleeve andpin are parts are respectively connected to the clevis andto the drawplate and when the moment comes for the separation of the plow from thetractor, the pin 74 and sleeve 77 separate so as to let the plow drop.The

telescopic connection ofthe lpin with the sleeve is necessary in orderto sustain the draw plate and draw bar 51 so that all of the weight doesnot come on the link 59 or the side arms 60 and 61, neither of which arecapable of any supporting function.

The reader will recognize thel connection of the dog 62 with the link72as being typical of all of the forms of the invention.

When the pull between the dog and link be' comes excessive the spring 68will yield, permitting the latch 67 to lower and thus release the dog.It is at this time that the pin 74 separates from the sleeve 77, theplow then halting while the tractor momentarily proceeds. -The dog 62 isintended to spin aroundv to the original engaging position with thelatch 67 iny readiness to again make connection with the link 7 2 whenthetractor is backed up and the pin 74 is re-inserted in the sleeve 77.Thehandle 76 aids this insertion. Before concluding, to Fig. 19. The dog116, here shown, is substantially like the dog shown in Figs. 1 and 5and its functions in respect to the pull link 117 are the same. However,the idea olf-the horn 44 in Fig. 7, is now incorporated in the dogitself.` The horn 118 is made integral with the dog 116 and stands outfar enough attention isdirected link-117 slipping back over.

W'hile the construction andarrangement of the improved automaticcouplingas herein described and claimed, is that vof a: gen* erally preferredform, obviously modifications and changes may be made without departingfrom the spirit of ythefinvention or l i beyondlthe pivot ofthe vdog toprevent the y auf latch in engagement with the under side of i the sidearms inposition to sustain the dog'. 2. A coupling comprising rasidearm,

dog pivoted thereupon, a pulling link which embracesthe side arm and aportionof thedog beneathv the pivot, and means residing in the-endstructure of the pivot to prevent 1 the link slipping back beyond thepivot.

3. A coupling comprising a 'pair of side arms, va dog pivoted betweenthe side arms, a pin bygwhich the dog is pivoted therebetween, alinkembracing the side arms and engaging the dog beneath the pivot pin, andmeans to prevent the link slipping back vbeyond the pivot and over theside arms comprising, an offset on one end of the pin and a washerhaving a projection on the other end of the pin.

'4. A coupling comprising a pair of side arms, a dog pivoted between theside arms, a pin by which the dog is pivoted therebetween, alinkembracing the side arms and engaging the dog beneath th'e pivot pin, andmeans to prevent the link slipping back beyond the pivotand over thesidel arms comprising an offset on one end of the pin and a washeryhaving a projection on the other end of the p'in,`said means comprisingside pieces forming a horn.

5. In combination with a clevis, plow beam and draw plate, a bracketattached to the plow beam having alink, a coupling connected between theclevisv and the link` including a dog with which the link hasengagement, means attached between the draw plate and-the clevis tosustain the plow beam` on the clevis independently of the coupling andlink, and means for preserving a predetermined position of the dog Vinrespect to the link until the tension between the dog and link becomesexcessive byv virtue of the pull' at the clevis thereupon releasing thedog to drop the plow beam.

6.,In combination with a clevis, plow y beam and draw plate, abracket'carried by the plow beam and having a link, a link extendingfrom the @levis carrying a dog with which the link engages, meanscarried by the draw plate for sustaining the plow beam on the clevisincluding a pin carried by the draw plate and a sleeve carried by theclevis said parts being in telescopi@ engagement, a latch for sustainingthe dog while the plow is being drawn at the clevis, and a spring forsustaining the latch until the pull preponderates the tension of thespring whereupon the dog is released to drop the link and plow beam,said pin thereupon disengaging from the sleeve.

7. A coupling comprising a pair of arms, means fastened between the armsto space them at one end, a dog permanently pivoted between the arms tospace them at the other end, one end each of the dog and spacing meansdefining a narrow passage between the arms, means for supporting Vsaidend of the dog including a bolt situated in 'and operable through thepassage, said bolt having a supporting head, and resilient means tendingto pull the bolt head through the passage.

8. A coupling comprising an arm attachable to a vehicle to be drawn, adog pivoted upon the arm, a bracket mounted upon the arm, meansconstituting a dog-supporting latch permanently rockable upon thebracket, resilient mea-ns for holding the latch in a supportingposition, and means by which the inluence ot' the resilient means istransferred to the latch.

9. A coupling comprising apair of arms, means fastened between the armsto space them at one end, a dog permanently pivoted between the arms tospace them at the other end, means constituting a bracket held in placeby the fastening means of the first spacingV means, frockably mountedmeans carried by the bracket for supporting one end ot' the dog, a boltcarried by said rockablemeans extending through the space between thearms, abuttable means carried by the free end 'of the bolt and resilientmeans interposed between said abuttable means and the arms.

10. In combination with a clevis, plow beam and draw plate, couplingmeans connecting the clevis and plow beam, and means connecting theclevis with the draw plate to sustain the plow beam on the clevisindependently ot' said coupling means.

1l. In combination with a devis, plow beam and draw plate, a separablecoupling between the clevis and the `plow beam, and telescopicallyconnected means carried by the clevis and draw plate to sustain the plowbeam on the clevis independently of said coupling means.

WILLIAM ANTON MUELLER.

